Non Abelian BF theories with sources and 2-D gravity

We study the interaction of non-Abelian topological $BF$ theories defined on two dimensional manifolds with point sources carrying non-Abelian charges. We identify the most general solution for the field equations on simply and multiply connected two-manifolds. Taking the particular choice of the so-called extended Poincar\'e group as the gauge group we discuss how recent discussions of two dimensional gravity models do fit in this formalism.Comment: 20 pages, Latex, To appear in Phys Rev D5

Evaluación del efecto tóxico de los extractos vegetales acuosos Barbasco (Phyllantus sp.) Neem (Azadirachta indica) y Marigol (Tagetes patula) sobre los microorganismos Trichoderma sp. y Metarhizium sp.

El experimento se llevó a cabo en el Laboratorio de Fitopatología del Centro de Investigación Natfaima de Corpoica, localizado en el municiplo de El Espinal, departamento del Tolima, entre los meses de marzo y agosto de 2003, Para la piueba se utilizaron extractos vegetales acuosos de Neem (Azadirachía indican), Marigol (Tagetes patula)] y Barbasco [Phylanthus ichihyomelhlus) y los microorganismos biocontroladores Irichoderma sp y Metarhizium so. Bajo condiciones de laboratorio se evaluaron cinco concentraciones (0%. 5%, 10%, 15% y 20%) de cada uno de los tres extractos Gicuosos, frente al crecimiento de los dos microorganismos biocontroladores. Se evaluaron las variables tasa de crecimiento (Crecimiento radial de los hongos biocontraladores) y el valor de la concentración mínima de inhibición. Se ulilizó un diseño completamente al azar y las observaciones se analizaron mediante pruebas de regresión y correlación. En conclusión se puede afirmar que ninguno de los tres extractos en las concentraciones evaluadas, afectan severamente a los hongos Metarhizium so. y Trichoderma sal y que tanto el Neern como el Margo! en concentaciones superiores al 20% puede lener un efecto funguiciaa contra el hongo Trchoaerma so. Igualmente con respecto a Marigel, es posible que en concentraciones más altas, tenga efectos tóxicos sobre el Metarhizlumn sp

Los DBA: Herramienta Pedagógica para la Intervención de las Dificultades de Aprendizaje en la Lectura

La investigación se enfoca en los errores detectados en las dificultades de aprendizaje (lectura), aplicada en el contexto urbano en la Ciudad de Pamplona, en el Instituto Técnico Arquidiocesano San Francisco de Asís, Sede Santa Marta y en el contexto rural en el municipio de Pamplonita, Norte De Santander en la I. E. Nuestra Señora del Pilar, Sede Camilo Daza ubicada en la Vereda San Rafael. El referente metodológico se enfoca en la investigación cualitativa, de tipo descriptiva, el método empleado es el estudio de casos, y el fenómeno que se aborda desde el enfoque cualitativo, son las Dificultades de Aprendizaje. la técnica de la entrevista de tipo estructurada. Los resultados evidencian que los docentes no implementan estrategias que faciliten la superación de las dificultades, y en ocasiones no se interesan por brindar el apoyo oportuno a los estudiantes durante el ejercicio del proceso lector

Free Abelian 2-Form Gauge Theory: BRST Approach

We discuss various symmetry properties of the Lagrangian density of a four (3 + 1)-dimensional (4D) free Abelian 2-form gauge theory within the framework of Becchi-Rouet-Stora-Tyutin (BRST) formalism. The present free Abelian gauge theory is endowed with a Curci-Ferrari type condition which happens to be a key signature of the 4D non-Abelian 1-form gauge theory. In fact, it is due to the above condition that the nilpotent BRST and anti-BRST symmetries of the theory are found to be absolutely anticommuting in nature. For our present 2-form gauge theory, we discuss the BRST, anti-BRST, ghost and discrete symmetry properties of the Lagrangian densities and derive the corresponding conserved charges. The algebraic structure, obeyed by the above conserved charges, is deduced and the constraint analysis is performed with the help of the physicality criteria where the conserved and nilpotent (anti-)BRST charges play completely independent roles. These physicality conditions lead to the derivation of the above Curci-Ferrari type restriction, within the framework of BRST formalism, from the constraint analysis.Comment: LaTeX file, 21 pages, journal referenc

The MINERν\nuA Data Acquisition System and Infrastructure

MINER$\nu$A (Main INjector ExpeRiment $\nu$-A) is a new few-GeV neutrino cross section experiment that began taking data in the FNAL NuMI (Fermi National Accelerator Laboratory Neutrinos at the Main Injector) beam-line in March of 2010. MINER$\nu$A employs a fine-grained scintillator detector capable of complete kinematic characterization of neutrino interactions. This paper describes the MINER$\nu$A data acquisition system (DAQ) including the read-out electronics, software, and computing architecture.Comment: 34 pages, 16 figure

First evidence of coherent K+K^{+} meson production in neutrino-nucleus scattering

Neutrino-induced charged-current coherent kaon production, $\nu_{\mu}A\rightarrow\mu^{-}K^{+}A$, is a rare, inelastic electroweak process that brings a $K^+$ on shell and leaves the target nucleus intact in its ground state. This process is significantly lower in rate than neutrino-induced charged-current coherent pion production, because of Cabibbo suppression and a kinematic suppression due to the larger kaon mass. We search for such events in the scintillator tracker of MINERvA by observing the final state $K^+$, $\mu^-$ and no other detector activity, and by using the kinematics of the final state particles to reconstruct the small momentum transfer to the nucleus, which is a model-independent characteristic of coherent scattering. We find the first experimental evidence for the process at $3\sigma$ significance.Comment: added ancillary file with information about the six kaon candidate

MINERvA neutrino detector response measured with test beam data

The MINERvA collaboration operated a scaled-down replica of the solid scintillator tracking and sampling calorimeter regions of the MINERvA detector in a hadron test beam at the Fermilab Test Beam Facility. This article reports measurements with samples of protons, pions, and electrons from 0.35 to 2.0 GeV/c momentum. The calorimetric response to protons, pions, and electrons are obtained from these data. A measurement of the parameter in Birks' law and an estimate of the tracking efficiency are extracted from the proton sample. Overall the data are well described by a Geant4-based Monte Carlo simulation of the detector and particle interactions with agreements better than 4%, though some features of the data are not precisely modeled. These measurements are used to tune the MINERvA detector simulation and evaluate systematic uncertainties in support of the MINERvA neutrino cross section measurement program.Comment: as accepted by NIM

Towards a Proof Theory of G\"odel Modal Logics

Analytic proof calculi are introduced for box and diamond fragments of basic modal fuzzy logics that combine the Kripke semantics of modal logic K with the many-valued semantics of G\"odel logic. The calculi are used to establish completeness and complexity results for these fragments